Certified Business Analysis Professional (CBAP) Practice Test 2025 – All-in-One Study Resource to Ace Your CBAP Exam!

The appropriate type of diagram for understanding a top-level process and its subprocesses is a functional decomposition diagram. This diagram breaks down complex processes into smaller, more manageable components, facilitating a clearer understanding of the hierarchical relationship between the main process and its various subprocesses.

While activity diagrams illustrate the flow of activities within a process, they are more focused on detailing the sequence and conditions for activities rather than showcasing the overall structure of a process and its components. State machine diagrams, on the other hand, describe the states of an object and how it transitions between those states, which does not directly align with visualizing subprocesses under a top-level process. Use case diagrams primarily focus on the interactions between actors and systems, outlining requirements rather than breaking down processes.

Therefore, the functional decomposition diagram is the most suitable choice for demonstrating how a top-level process is divided into its respective subprocesses.